Stainless Steel 310S Annealed
Temper
AISI/SAE 310S · UNS S31008 · EN 1.4845, X8CrNi25-21 · JIS SUS310S · GB 06Cr25Ni20, 0Cr25Ni20
Use for annealed bar, forgings and fittings where full ductility and weldability are needed but section is too heavy for sheet practice.
Values for the Annealed condition
Other 310S tempers and conditions
310S is listed in 5 conditions; see the grade overview at 310S.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedThis page mill-annealed bar/forging condition (ASTM A276/A479) | Use for annealed bar, forgings and fittings where full ductility and weldability are needed but section is too heavy for sheet practice. | 255 | 570 | 45 | 170 HB | 2.2 % IACS |
Solution AnnealedDefault 1050–1120 °C, rapid cool (plate/sheet/tube standard supply) | Standard as-supplied condition for plate, sheet and tube; maximum ductility, corrosion resistance and freedom from sigma/carbide precipitation. | 260 | 590 | 45 | 160 HB | — |
hot worked bar and plate, descaled (not re-annealed) | Economical heavy bar and plate for furnace structural parts where surface finish and dimensional tolerance are secondary. | 275 | 580 | 42 | 180 HB | 2.2 % IACS |
cold-finished bar/wire, light cold work | Pick for tighter tolerance bar, better surface and higher room-temperature strength; ductility and creep-service benefit are reduced. | 520 | 760 | 25 | 22 HRC | — |
heavily cold-drawn/rolled strip and bar | For springy strip, fasteners and high-strength room-temperature parts; not used for high-temperature service because cold work is lost on heating. | 690 | 930 | 12 | 28 HRC | 2.2 % IACS |
What is 310S Annealed?
310S Annealed is 310S in the Annealed temper — use for annealed bar, forgings and fittings where full ductility and weldability are needed but section is too heavy for sheet practice. 310S Annealed has a yield strength of 255 MPa (37 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 87% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi). 310S Annealed has a density of 7.98 g/cm³ (0.288 lb/in³), heavier than 85% of stainless steel grades. It melts at 1,400°C (2,552 °F). Solution Annealed is the default condition FabDigit quotes; Annealed is available on request or by drawing note.
Advantages
- High service temperature — 1,050°C (1,922 °F), better than 91% of stainless steel grades
- Forms and bends easily — 70/100, better than 79% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- High embodied carbon — 6.5 kg CO₂/kg, worse than 93% of stainless steel grades
- Low strength — 255 MPa (37 ksi), worse than 87% of stainless steel grades
310S Annealed properties
Typical room-temperature values for 310S Annealed; 23 are specific to this condition. Other listed values are 310S reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
310S Annealed has a density of 7.98 g/cm³ (0.288 lb/in³), heavier than 85% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical15
310S Annealed has a yield strength of 255 MPa (37 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 87% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
310S Annealed is rated for continuous service to 1,050°C (1,922 °F). It conducts heat at 14.2 W/m·K (8.2 BTU/hr·ft·°F), worse than 76% of stainless steel grades. Thermal expansion is 15.9 µm/m·K (8.83 µin/in·°F).
Electrical3
310S Annealed conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (66/100), better than 59% of stainless steel grades.
Sustainability4
Producing a kilogram of 310S Annealed takes about 85 MJ of energy and emits 6.5 kg of CO₂ — more than 92% of stainless steel grades. Typical recycled content is 55%.
Manufacturability8
310S Annealed's machinability is poor (32/100, worse than 62% of stainless steel grades); weldability very good (75/100); formability very good (70/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 310S Annealed
Is 310S easy to machine?
Gummy and strongly work-hardening: use rigid setups, positive-rake sharp carbide, ~30–60 m/min surface speed, heavy feed, no dwell, and flood coolant.
Can 310S be welded?
Readily welded by GTAW/GMAW/SMAW with matching 310/ER310 filler; keep heat input low, no preheat or PWHT, avoid long exposure at 650–900 °C to prevent sigma embrittlement.
Can 310S be formed, bent or molded?
Good cold formability but high work-hardening rate demands ~50% more press force than 304; hot work at 1150–1200 °C and re-solution anneal after heavy forming.
What surface finishes work on 310S?
Not anodizable — pickle and passivate or electropolish after welding to restore the oxide; grinds and polishes to bright finishes, glass-bead or shot blast for furnace parts.
310S chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| C0.08 max (310S vs 0.25 max for 310) | ≤ 0.08 | 0.05 |
| Cr | 24 – 26 | 25 |
| Ni | 19 – 22 | 20.5 |
| Mn | ≤ 2 | 1.2 |
| Si1.00 max in some EN/JIS deliveries | ≤ 1.5 | 0.6 |
| P | ≤ 0.05 | 0.03 |
| S | ≤ 0.03 | 0.01 |
| NEN 1.4845 limit | ≤ 0.11 | 0.04 |
| Fe | balance |
310S Annealed — frequently asked
What is 310S Annealed used for?
310S Annealed is typically used for welded furnace muffles, heat-treatment baskets and trays, radiant tubes and burner nozzles, furnace retorts and liners, boiler and incinerator internals and annealing box covers. In short: furnace-grade austenitic stainless.
What is the yield strength of 310S Annealed?
310S Annealed has a typical yield strength of 255 MPa (37 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 87% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is 310S Annealed easy to machine?
Not especially — machinability is rated poor (32/100, worse than 62% of stainless steel grades). Gummy and strongly work-hardening: use rigid setups, positive-rake sharp carbide, ~30–60 m/min surface speed, heavy feed, no dwell, and flood coolant.
Can 310S Annealed be welded?
Yes — weldability is rated very good (75/100). Readily welded by GTAW/GMAW/SMAW with matching 310/ER310 filler; keep heat input low, no preheat or PWHT, avoid long exposure at 650–900 °C to prevent sigma embrittlement.
What surface finishes work on 310S Annealed?
Not anodizable — pickle and passivate or electropolish after welding to restore the oxide; grinds and polishes to bright finishes, glass-bead or shot blast for furnace parts.
Can 310S Annealed be formed, bent or molded?
Good cold formability but high work-hardening rate demands ~50% more press force than 304; hot work at 1150–1200 °C and re-solution anneal after heavy forming.
What is the maximum service temperature of 310S Annealed?
310S Annealed is rated for continuous use to about 1,050°C (1,922 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 310S Annealed?
Yes — 310S Annealed is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM A240/A240M — Cr and Cr-Ni Stainless Plate, Sheet and Strip — ASTM International (2023)
- ASTM A276/A479 — Stainless Steel Bars and Shapes — ASTM International (2022)
- EN 10095 — Heat resisting steels and nickel alloys (1.4845) — CEN (2018)
- JIS G 4304 / GB/T 4237 (SUS310S / 06Cr25Ni20) — JISC / SAC (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Outokumpu Steel Handbook / 4845 datasheet — Outokumpu (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.